|Scania Streamline G-series unit. Click to enlarge.|
Scania unveiled its new Streamline series of trucks that will enable customers to reduce fuel consumption by up to 8%.
The Scania G- and R-series long-haulage trucks feature new low-drag looks and full air deflector kits. Potential fuel savings in long-haulage are up to 8% with the new, more efficient second-generation Euro 6 engines. Corresponding savings for Euro 3/4/5 are up to 5%.
Euro 6 Engines
Scania is introducing new Euro 6 engines with features that further boost efficiency. Second-generation 450 hp (336 kW) and 490 hp (365 kW) Euro 6 engines provide fuel savings of up to 2%. A unique, SCR-only 410 hp (306 kW) six has an extra economic edge. New 520 hp (388 kW) and 580 hp (433 kW) Euro 6 V8s provide extra performance. Proven EGR and SCR technologies are combined to provide optimum performance in all market segments.
Scania customers now have a choice of nine Euro 6 outputs, ranging from the 250 hp 9-liter unit to the 580 hp V8. Additional outputs will follow. In addition there are two gas engines, adaptable to run on biogas, compressed natural gas (CNG) or liquefied LNG.
V8s. The only Euro 6 V8s in the market, the new engines are based on the 16.4-liter platform introduced with the 730 hp unit. Like Scania’s inline 13-liter engines, the new V8s have torque-to-power ratios in excess of 5.
520 hp, 2,700 N·m at 1,000-1,300 r/min, EGR+SCR
580 hp, 2,950 N·m at 1,000-1,350 r/min, EGR+SCR
730 hp, to be released later
The performance of the new 580 hp Euro 6 V8 is similar to the 620 hp Euro 5 thanks to its wider torque peak and ‘fat’ power curve. Fuel consumption of a Euro 6 V8 engine worked hard is equivalent to Euro 5. The exhaust brake output is 320 kW at 2,400 r/min.
Scania’s Euro 6 V8 engines feature common-rail fuel injection (Scania XPI) and a variable-geometry turbocharger (VGT) mounted at the rear. A newly-developed water-cooled EGR system is fitted low down underneath the RH cylinder bank. The silencer unit for the V8 engines is somewhat larger with higher capacity than for inline engines. The top-output 730 hp V8 is due for release by the time Euro 6 becomes mandatory.
6-cylinders. Four 12.7-liter engines constitute Scania’s six-cylinder Euro 6 offering.
370 hp, to be released later
410 hp, 2,150 N·m at 1,000-1,300 r/min, SCR (see below)
450 hp, 2,350 Nm at 1,000-1,300 r/min, EGR+SCR
490 hp, 2,550 N·m at 1,000-1,300 r/min, EGR+SCR
The 450 and 490 hp engines are based on further refinements of the 440 and 480 hp units, which have been proven in the hands of operators since early 2011. The 450 hp engine is available in P-, G- and R-series and the 490 hp unit in G- and R-series trucks.
The 450 and 490 hp engines have been further developed in several respects, including the engine management system and a revised intake system that maintains sufficiently high exhaust temperatures without the need for an intake throttle.
The exhaust brake is rated at 256 kW at 2,400 r/min. A new disengaging air compressor is being introduced across the Euro 6 engine range. The compressor has a pneumatically-controlled coupling that disengages when the compressor is idling, contributing to a fuel saving of up to 1%, depending on operation.
Euro 6 trucks for long-haulage should generally be specified for highway cruising at less than 1,200 r/min to minimize fuel consumption, Scania says. The high torque delivered already from low revs in combination with automated gearchanging means that the low cruising revs save fuel without requiring extra attention from the driver. Tests have shown that Scania’s second-generation Euro 6 engines are 2-3% more economical than the first ones.
410 hp fuel-saver with only SCR. The 410 hp engine has been developed to manage Euro 6 using only SCR technology. A fixed-geometry turbocharger and an electric intake throttle are used. Without EGR piping, the auxiliary systems are somewhat simpler and there is a weight saving of 40 kg compared to an engine with EGR and SCR, some of which is likely to be used to carry more AdBlue on-board. The exhaust aftertreatment system remains unchanged, with the same compact silencer unit as for other 5- and 6- cylinder Euro 6 engines.
The 410 hp 13-liter produces maximum torque all the way down to 1,000 r/min. The engine is around 3% more economical than the 400 hp Euro 5 EGR engine. AdBlue consumption of Scania’s Euro 6 engines with only SCR is limited to around 6% of diesel consumption. The corresponding figure for an engine with EGR and SCR is around 3% or somewhat higher at very high load, high altitude or in cold weather.
5-cylinder Euro 6 engines. The range presented earlier at IAA 2012 comprises four diesel engines and two gas engines, with an ethanol engine in the pipeline.
250 hp diesel, 1,250 N·m at 1,000-1,350 r/min, EGR+SCR
280 hp diesel, 1,400 N·m at 1,000-1,350 r/minEGR+SCR
320 hp diesel, 1,600 N·m at 1,050-1,300 r/min, SCR
360 hp diesel, 1,700 N·m at 1,100-1,350 r/min, SCR
280 hp gas/biogas, 1,350 N·m at 1,100-1,400 r/min
340 hp gas/biogas, 1,600 N·m at 1,100-1,400 r/min
280 hp ethanol, to be released later
The 320 and 360 hp 9-liter engines with only SCR are optimized for cruising at higher revs and can be geared for economical cruising between 1250 and 1350 r/min. The exhaust brake produces 190 kW at 2,400 r/min.
For Euro 6 applications where engines seldom run at full load, Scania recommends that customers consider going for a somewhat lower engine output than for Euro 5. Working the engine a little harder will benefit efficiency, since a high exhaust temperature can be maintained more easily. If the exhaust temperature is getting too low, extra fuel will be burnt to keep the aftertreatment system working properly. Similarly, leaving the engine idling will risk cooling down the aftertreatment system.
Aftertreatment principles. The equipment on the engine varies between engines with EGR+SCR and engines with SCR only. An electrical intake throttle is used on 250, 280, 320, 360 and 410 hp engines, whereas the new 450 and 490 hp 13-liter engines and 520 and 580 hp V8 engines manage without it. For extra heat management, the two 9-liter engines with EGR and SCR have an extra injector to spray diesel into the exhaust.
Scania Opticruise with Performance Modes
Numerous new features, including Scania Active Prediction, have been integrated with Scania Opticruise into a predictive powertrain control system that provides fuel savings of 4-5%. Specialized performance modes have been developed to boost efficiency in different applications. A basic version of Scania Opticruise is an additional option for maximum fuel economy. With limited functionality, it further simplifies economical driving.
Further fuel savings are obtained from the aerodynamic refinements introduced with Scania Streamline, low-drag gearboxes and the second generation 450 and 490 hp Euro 6 engines.
Scania Active Prediction is a predictive cruise control system that uses GPS and topographical map data to finely regulate the cruising speed. It is fully integrated in the new functionality, using different fuel-saving strategies in different performance modes. The new version of Scania Ecocruise is fitted in markets where no topographical map data is available.
The new performance modes enable customers to tailor the vehicle’s performance to suit each type of operation, as well as to individual preferences regarding functionality and driver influence. All settings can be altered or fine-tuned by a Scania workshop.
Modes. Up to three performance modes can be specified on vehicles with Scania Opticruise. Several other parameters can be set individually according to customer needs and all settings can be altered by a Scania workshop.
Standard mode is an all-round mode optimized to provide good fuel economy, while still delivering good hill performance. The system strives to run the engine at maximum torque during hill-climbing.
Scania Active Prediction is fully integrated in the functionality, increasing speed slightly to gain momentum before entering an uphill section. Before entering a descent, the vehicle starts coasting to save fuel, and gains downhill speed using the momentum of the vehicle. The system works within a speed window of 6% below and 4% above the set cruising speed (–6%, +4%).
Economy mode is tuned to consume as little fuel as possible with some sacrifice in terms of trip time. Engine response is soft (with Euro 6 engines). Alternative speed limiter settings of 85 or 80 km/h (53 or 50 mph) can be chosen, which engage automatically when switching to Economy mode. Kickdown is disabled.
Scania Active Prediction uses a special economy strategy. The speed window spans from 12% below up to the set cruising speed (–12%, 0%). The minimum adjustable offset for downhill speed control with a retarder is 5 km/h above cruising speed in Economy mode (3 km/h in other modes).
Power mode is intended for runs where transport time is at a premium. Engine response is aggressive (Euro 5 with XPI, Euro 6 engines) and uphill performance is optimized by running the engine at maximum power, with slightly quicker gearchanges than in Standard mode. Scania Active Prediction is not available and the cruise control has normal functionality.
Off-road mode is suitable for driving in rough terrain and on surfaces with high rolling resistance. Vehicles specified for off-road driving have Off-road mode and it can be specified for other applications as well, for example forestry. Engine response is soft (Euro 5 with XPI, Euro 6 engines) to promote smooth progress.
The system strives to keep the clutch engaged as much as possible to avoid interruptions in power delivery and traction. The number of gearchanges is minimised by allowing the engine to work over a wider rev band. Gearchanges are faster with a priority on gearchanging speed over comfort. Scania Active Prediction is not operating, normal cruise control functionality applies.
Basic version of Scania Opticruise with limited functionality. Scania has also developed a simplified gearchanging system that limits the possibilities for the driver to influence gearchanging. This shortcut to even better fuel economy is requested in particular by large fleet owners, whose drivers frequently drive different brands.
Scania Opticruise Basic for long-haulage:
- Fully automated Scania Opticruise (with automatic clutch).
- Standard and Economy mode.
- Scania Active Prediction (or Scania Ecocruise).
- Speed limiter set at 85 km/h or 80 km/h.
- Kickdown disabled.
- Manual gearchanging disabled (above 50 km/h).